Steam superheater for steam engines



' y1,613,230 Feb. 22,1927. W SCHMIDT Y STEAM SUPERHETER FOR STEAM ENGINES Filed Deo. l5, 1920 4 Sheets-Sheet l 'Enki @Ink-f5- o o oooooooooo ooooo 000 ooooooooo ooooo l goo oooo oooo OOO Mem

.4 TORNEYS n l 618,230 Feb. 22, 1927. W. SCHMIDT STEAM SUPERHEATER FOR STEAM ENGINES Filed Dec. l5. 1920 4 Sh-eetSjSheGt 2 Fig.h Zas A gwuwntoz WILHELM SCHMIDT wir Inoltre? W. SCHMIDT STEAM SUPERHEATER FOR STEAM ENGINES Feb. 22, 1927. 1,618,230

,Filed Dec. l5, 1920 4 Sheets-Sheet 5 /ft//L f/a/w 5CH/w07 www y l 8,

(www

A TTOHNEYS Feb. 22,'1927. 1,618,230

W. SCHMIDT STEAM SUPERHEATER FOR STEAM ENGINES A TTUH/VEYS Patented Feb. 22, 1927. i

UNITED STATES 1,618,230 PATENT oFFIcE.

WILHELM SCHMIDT, OF CASSEL-WILHELMSHOHE, GERMANY; SIMON HOFFMANN, OF

CASSEL-WILHELMSEOHE, GERMANY, EXECUTOR OF SAID WILHELM SCHMIDT, DE- CEASED, ASSIGNOR TO SCHMIDTSCHE HEISSDAMPF G. M. B. H., OF CASSEL-WIL- HELMSHOEHE, GERMANY, A CORPORATION OF GERMANY.

STEAM SUPERHEATER FOR STEAM ENGINES.

Application led December 15, 1920, Serial No. 431,052, and in Germany July'1'0,` 1919.

medium, for heating the water from which lthe -live steam is produced. It 'is to be understood that the term working steam may mean either the live steam from 'the boiler-or the partially-expanded steam between two stages of a compound steam engine.

In the accompanying drawings, I have illustrated several forms of construction ofk the present invention. I

Fig. 1 shows at the left hand portion a front elevation and at tne right hand portion a section according to the line (z-b of Fig. 2 and illustrates a marine boiler having three flues of the return vflue character, the furnace being located atfone side 'as shown best in Fig/2 which is a longitudinal section according to line c-d of Fig. 1; Fig. 2a is a diagrammatic elevation with parts in section,

illustrating aplant embodying my invention,

for superheating the live steam from the boilq er and also the partially-expanded steam on its passage from the high-pressure cyhnder of a 'compound engine ,to the low-pressure cylinder. Figs. 3 andfl are vertical sectlons taken perpendicular to each other and showing the superheating steam generator upon an enlarged scale. Fig. 5 is a cross-section of a water ytube boiler to whioh1my invention has been applied. Fig. 6 is a front elevation of the upper drums of said construction, and Fig. 7 a section according to line e-f of Fig. 6. Figs. 8 and 9 are sections taken at right angles to each other and illustrating the details of a regulating valve. and Fig..

10 is a section on line g-h of Fig. 8.

IVhil'e in Figs. 1 and 2 I have illustrated a boiler fired from one side only, it willl be obvious that the arrangement may be readily adapted to boilers fired from both sides. In

continuous Wall.

this case, two boilers, each lired from one side, will be arranged back to back with a 55 suitable space between them and in this space would be located the superheating steam generator which, therefore, in this particular case, would be heated from both sides.

The generator of superheating. steam con- .60

sists'ot1 two drums or headers 1-2 and water tubes 3 connecting them. In order that the Water tubes may form a continuous surface and yet be reliably connected with the headers 1 2, the ends of the said tubes 3 65 are alternately bent in opposite directions as shown in Figs. 2 and 3. These tubes, therefore, form a continuous wall or water back but it will be obvious that, if desired,

the headers 1*2 may be 'connected by other 70 tubes in vaddition to those forming the said The superheating vsteam produced in this generator passes out through a connection 4. The hot gases produced inthe furnace lues 6 pass, as indi- 75 cated by the arrows, into the three comparte` ments J of the combustion chamber and then.l through the return tubes '11 to the stack 12. During this travel, the hot gases give off part nf their heat to the water wall formed 89 by the tubes 3 and to the water contained in said tubes. A portion of the radiant heat ot' the furnace is also absorbed by the superheating steam generator. The pressure will thus rise rapidly and when it has attained, a certain figure, as for instance, 10() atmospheres, the stokenwillopen a regulating valve 18 which controls the connection from the steam outlet 4 to a pipe 17 connected with the heating coil 21 which is lo- 90 cated in the water' space of thexl main boiler 10. The valve 19 which I have shown between the outlet 4 and the regulating valve 18 is open under normal circumstances and is shut 'only when'repairs are to be made 95 The valve 20 or an emergency occurs. shown at the other side ofthe outlet 4 is kept closed while starting the operation. AnyI suitable mechanism may be employed for controlling valve 18, for instance, a hand v.wheel 13, and bevelled gearing 15-16. As

shown the shaft of the hand wheel 13 has a'v threaded portion 14a journalled in a .smooth stationary bearing 14 and carryina 5 nut or looking wheel 14 adapted tol screwed tightly 'against the bearing 14 for the purpose of locking said shaft after ad- ]ustment.' Even the lowest portions of the coils 21 lie above the level of the water in the upper header 1V as indicated in Fig. 2; thus any water resulting from the condensation of steam Within said coils will return to the superheating steam generator through the pipe 22 which leads from the outlet of the coil -21 to the water space of said generator. By this operation of the valve 18, I prevent excessive heating of the generator when the operation is started.

After a normal condition has been obtained the valve 18 is closed and the valve 20 is opened. In this case the steam from the generator 1, 2, 3 will pass through the o'utlet 4 and the valve 20 to a conduit 23 leading to the steam superheater. ,This superheater has been indicated diagrammatically in F ig. 2a as comprising two separate paths 5 and 7 res ectively, through one of which is conducte the steam coming from the pipe 23 and returning to the generator through a pipe 24 and through the pipe 22. Through the other path 7 is conducted the steam to be superheated. This steam may be either the live steam direct from the boiler (in the case of the left-hand superheater in Fig. 2a) or, as illustrated in said ligure at the right, it may be the steam which is on its way from one stage 8 of a steam engine (reciprocating engine or turbine) to the subsequent stage 8 of such engine. The superheater proper indicated at 5-7 may be of any well nown and approved construction to insure a proper transfer of the heat from the superheatingpsteam circulating through the pipes 23-24 `to the working steam. It is desirable to arrange the superheater at such a level that the condensation product will automatically flow by gravity into the pipe 24 and return to the lower header 2through the pipe 22. Of course, the superheater might be located at alower level but in this case it would be necessary to provide a pump or other device for returning the condensation product to the generator. For the sake of safety, a double safety valve 25 is provided and in case the allowable maximum pressure is exceeded, this valve will -open and allow the excess steam to be blown oil' .into the main boiler 10 through a pipe 26. As long as these valves remain closed, the

- same amount of water 'will circulate in the path connected with the generator and there will be no necessity of replenishing unless, through carelessness of the attendant. the pressure is allowed to rise so high'that the safety valves 25` will open. I have not indicated any means for su plying water to this generator, but it wil be understood that any of the well known pumps or injectors may be employed for this purpose.

. An arrangement suitable for water tube boilers is illustrated in Figs. 5, 6 and 7,

constitutes a partition within the combustion chamber so that this partition isexposed from both sides tothe radiant heat' of the furnace. A very efficient h'eating action is thus obtained. At. 21 I have indicated heating coils located within fthe water space of the upper boilerdrums and it will be understood that the connections are substantially the same as in the construction first described. When starting the valve 420 is closed; the valve 19 is normally open, and is never closed except for repairs or in case of emergency. lVhen the pressure within the generator formed 'by the l1eaders`1-2and tube 3 eX- cceds a certain limit, a valve 18" will open automatically and will allow the steam produced in the generator to pass through the pipe 17 into the coils 21, thus heatingthe water in the boiler, the condensation products flowing from saidl coils through the pipe 22 to the upper drum or header 1 of the generator. In this case also the water level in the generator is below the lowermost point of the coils 21. As soon as a proper running condition has been attained,. the valve 20 is opened, the superheating steam .passes through the pipe 23 to the lsuperheater as before and the condensation products return through the pipes 24 and 22 to the generator.- For the sake of greater safety, a double safet valve 25 is provided in this case also; shou d the automatic regul lating valve 18 fail to act, the valve 25 will open and allow steam to pass from the outlet 4 to the steam space of the main boiler through pipe 26.

The automatic regulating valve l18 may be constructed in detail as shown in Figs.

8, 9 and 10. The" casing 27 is divided linto two compartments by a partition 28 and a bushing 29. In this bushing is adapted to slide a tubular valve 30, which, inthe position illustrated, covers two sets of slots or ports 31,provided in the bushing. The slide valve 30 is secured 'to aV spindle 32 having a steam tight lit within a guide' 33 vand 'extending tovvthe, outside. -'l`he" upper the passage through the valve casing is closed. The inlet of the casing shown at the left in Fig. 8l is connected with the superheating steam generator, through the 'outlet l and valve 1,9 and the outlet of the casing 27 shown at the right in Fig. 8 is connected with the heating coils 2l', through the pipe 17. Normally the valve 30 is closed as shown, the tension of the spring 35 being such as to exactly balance the pressure of the steam acting on the lower end of the spindle 32, under normal conditions, said spindle acting as a piston sliding in the guide 33. Should the steam pressure rise beyond the point at which it balances the action of the spring 35, the valve 30 will rise, thus opening a path through the slots 31 and allowing the excess of steam to pass to the heating surfaces 2l in the boiler so that the water in the boiler is heated while the steam in the coils 21 is condensed, the condensation waterv returning to the generator. Obviously, the greater the steam pressure, the higher Will the valve 30 rise and the greater will be the cross-section of the passage aorded to the steam. It, forinstance, when starting the operation, no heat is given oil' to the superheaters, the valve 30 willbe fully opened.

By means of this regulating device, the pressure within the superheating steam generator may be maintained automatically substantially constant; that is to say` the variations will be only a few atmospheres. It will be obvious that the spring 35 need notact directly on the valve spindle 32 but might operate through some intermediate mechanism; likewise, instead of the spring, I might employ a weight. f

Various changes in the specifi." form shown and described may be made without departing from the spirit of my invention, as set forth in the appended claims.

I claim:

l. A steam superheating arrangement comprising a generator of a gaseous superheating medium, a superheatcr having one path to receive the medium to be heated. and a separate path with an inlet to receive the superheating medium from said generator and an outlet having a return connection to said generator, and a heat-transfcrring device having a heating path with an inlet connected with the superheating n'iedium outlet of said generator, to receive excess superheating medium therefrom, and an outlet-having a return connection to said generator.

2. A steam superheating arrangement comprising a generator of a gaseous superheating medium, with an outlet for the exit of such superheating medium, a superheater haring two separate paths. one for 'the passage'of the medium to be heated, a connection leading from said outlet of the generator to the inlet of the other superheater path,

to convey superheating mediumto such other path, a heat-transferring device having a heatlng path the inlet of which is connected with the vabove mentioned connection at a point between the superheating medium out' superheating steam, a superheater having a connection receiving steam from said boiler, and another connection receiving steam from said generator to superheat steam generated in said boiler, a circuit extending from said generator through the water space ot said boiler and returning to said .generator, that portion of said circuit which lies within the boiler being positioned above the level of the water in said generator, to cause the condensation products to return to said generator by gravity flow, and a reliefvalve governing the iiow through said circuit.

4. A steam superheating system comprising a steam boiler, a generator of ,superheating steam, a superheater having connection with the steam space ot said boiler, a heatexchange device in said boiler, a closed circuit connecting said generator with said superheater, a parallel closed circuit connecting said generator and said heat-exchange device, and a relief valve in said parallel circuit adapted to open the same when the pressure therein exceeds a certain value.

5. A super heating arrangement comprising a boiler, a generator of a gaseous superheating medium, a superheater having one path to receive the medium to be heated and another path, adapted to receive the superheating medium fromsaid generator, a connection between the outlet of said secondnamed path and said generator, a heat-transferring device having its inlet connected t0 the superheating medium outlet of Said generator, a relief valve between the outlet of said generator and said inlet, a returnI connection from said heat-transferring device to said generator, a connection between said generator and said boiler, and a safety valve normally closing said last mentioned connection.

In testimony where-of I have hereunto set my hand.

lWILHELM SCHMIDT. 

